Single-ply membrane sheeting typically used for roofing and pond liners, or the like, incorporate a single-ply polymeric membrane as a water barrier. As it is impractical to manufacture sheeting which is large enough to cover entire roofs or ponds, individual sheets are adhered together along lap seams to form a continuous water impervious sheet which covers the roof.
In the past the lap seams have been completely formed at the construction site. This requires that, when necessary, the overlapping edges be cleaned, a primer applied and then an adhesive. A pressure sensitive adhesive seam tape is frequently used to form a lap seam. These are very tacky. Upon contact they adhere to the sheeting.
In order to reduce on-site labor, it is desirable to have the seam tape preapplied to the roofing membrane. In order to apply the seam tape to the edge of the sheeting, the edge of the sheeting is generally first coated with a primer which is allowed to dry and then the seam tape is applied to the edge of the sheeting. It is very important that the seam tape be precisely aligned with the edge of the sheeting.